Not going to name names, but I've seen this with packages I've worked
on: I put a lot of effort into cleaning things up, making things robust,
getting docs to build, tests to pass, collaborating with upstream,
fixing reverse dependencies, and then someone spends a few minutes to
upload a new version with total disregard for what the other
maintainer(s) were doing.
Things like "oh, documentation doesn't build anymore, I'll just disable
it", rather than fixing it. Or "oh, these tests don't pass anymore, I'll
just disable them", rather than looking into the regression. "Oh, my
upload triggered a transition, I'm no longer interested in this".
(This are all things that have happened to me.)
All that stuff is then left for others to clean up. And if one is
unlucky enough, this doesn't just cause work for the package, but for
all reverse dependencies.